UndefinedObject.st
changeset 1868 1cd4273ea11b
parent 1803 754f9205b651
child 1958 d8d575552c87
equal deleted inserted replaced
1867:e92d90126094 1868:1cd4273ea11b
   239     ^ self nilSubclass:(thisContext selector) args:(thisContext args)
   239     ^ self nilSubclass:(thisContext selector) args:(thisContext args)
   240 ! !
   240 ! !
   241 
   241 
   242 !UndefinedObject methodsFor:'testing'!
   242 !UndefinedObject methodsFor:'testing'!
   243 
   243 
       
   244 ? defaultValue
       
   245      "if the receiver is nil, return the defaultValue;
       
   246       otherwise, return the receiver.
       
   247       This method is redefined from Object;
       
   248       the argument is retuned unconditionally here.
       
   249 
       
   250       Can be used to provide defaultValues to variables,
       
   251       as in:
       
   252         foo := arg ? #defaultValue
       
   253      "
       
   254 
       
   255     ^ defaultValue
       
   256 
       
   257     "
       
   258      1 ? #default
       
   259      nil ? #default 
       
   260     "
       
   261 
       
   262     "Created: 4.11.1996 / 20:37:09 / cg"
       
   263     "Modified: 4.11.1996 / 20:41:53 / cg"
       
   264 !
       
   265 
   244 basicSize
   266 basicSize
   245     "return the number of indexed instvars
   267     "return the number of indexed instvars
   246      defined here since size in Object ommits the nil-check"
   268      defined here since size in Object ommits the nil-check"
   247 
   269 
   248     ^ 0
   270     ^ 0
   287 ! !
   309 ! !
   288 
   310 
   289 !UndefinedObject class methodsFor:'documentation'!
   311 !UndefinedObject class methodsFor:'documentation'!
   290 
   312 
   291 version
   313 version
   292     ^ '$Header: /cvs/stx/stx/libbasic/UndefinedObject.st,v 1.26 1996-10-22 19:38:13 cg Exp $'
   314     ^ '$Header: /cvs/stx/stx/libbasic/UndefinedObject.st,v 1.27 1996-11-04 19:43:37 cg Exp $'
   293 ! !
   315 ! !